A187808 - cp's OEIS frontend

A187808 a(n) = |{0<=k n(n-k)-1, n(n+k)-1 are all prime}|.

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	3
7	1
8	2
9	1
10	3
11	2
12	3
13	1
14	4
15	1
16	4
17	1
18	3
19	2
20	5
21	4
22	4
23	2
24	4
25	1
26	4
27	2
28	5
29	1
30	4
31	2
32	4
33	2
34	6
35	2
36	5
37	4
38	4
39	2
40	5
41	1
42	7
43	1
44	7
45	5
46	3
47	2
48	4
49	2
50	4
51	3
52	6
53	3
54	6
55	4
56	7
57	4
58	8
59	2
60	9
61	2
62	8
63	3
64	2
65	3
66	7
67	4
68	7
69	1
70	7
71	4
72	7
73	1
74	7
75	4
76	9
77	7
78	8
79	2
80	9
81	3
82	6
83	2
84	6
85	3
86	7
87	2
88	8
89	3
90	7
91	4
92	6
93	8
94	9
95	4
96	6
97	3
98	9
99	5
100	8

[0, 1, 1, 2, 1, 3, 1, 2, 1, 3, 2, 3, 1, 4, 1, 4, 1, 3, 2, 5, 4, 4, 2, 4, 1, 4, 2, 5, 1, 4, 2, 4, 2, 6, 2, 5, 4, 4, 2, 5, 1, 7, 1, 7, 5, 3, 2, 4, 2, 4, 3, 6, 3, 6, 4, 7, 4, 8, 2, 9, 2, 8, 3, 2, 3, 7, 4, 7, 1, 7, 4, 7, 1, 7, 4, 9, 7, 8, 2, 9, 3, 6, 2, 6, 3, 7, 2, 8, 3, 7, 4, 6, 8, 9, 4, 6, 3, 9, 5, 8]

cp's OEIS Frontend

A187808 a(n) = |{0<=k n(n-k)-1, n(n+k)-1 are all prime}|.

Table of values

List of values

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	3
7	1
8	2
9	1
10	3
11	2
12	3
13	1
14	4
15	1
16	4
17	1
18	3
19	2
20	5
21	4
22	4
23	2
24	4
25	1
26	4
27	2
28	5
29	1
30	4
31	2
32	4
33	2
34	6
35	2
36	5
37	4
38	4
39	2
40	5
41	1
42	7
43	1
44	7
45	5
46	3
47	2
48	4
49	2
50	4
51	3
52	6
53	3
54	6
55	4
56	7
57	4
58	8
59	2
60	9
61	2
62	8
63	3
64	2
65	3
66	7
67	4
68	7
69	1
70	7
71	4
72	7
73	1
74	7
75	4
76	9
77	7
78	8
79	2
80	9
81	3
82	6
83	2
84	6
85	3
86	7
87	2
88	8
89	3
90	7
91	4
92	6
93	8
94	9
95	4
96	6
97	3
98	9
99	5
100	8

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	3
7	1
8	2
9	1
10	3
11	2
12	3
13	1
14	4
15	1
16	4
17	1
18	3
19	2
20	5
21	4
22	4
23	2
24	4
25	1
26	4
27	2
28	5
29	1
30	4
31	2
32	4
33	2
34	6
35	2
36	5
37	4
38	4
39	2
40	5
41	1
42	7
43	1
44	7
45	5
46	3
47	2
48	4
49	2
50	4
51	3
52	6
53	3
54	6
55	4
56	7
57	4
58	8
59	2
60	9
61	2
62	8
63	3
64	2
65	3
66	7
67	4
68	7
69	1
70	7
71	4
72	7
73	1
74	7
75	4
76	9
77	7
78	8
79	2
80	9
81	3
82	6
83	2
84	6
85	3
86	7
87	2
88	8
89	3
90	7
91	4
92	6
93	8
94	9
95	4
96	6
97	3
98	9
99	5
100	8

n	a(n)
1	0
2	1
3	1
4	2
5	1
6	3
7	1
8	2
9	1
10	3
11	2
12	3
13	1
14	4
15	1
16	4
17	1
18	3
19	2
20	5
21	4
22	4
23	2
24	4
25	1
26	4
27	2
28	5
29	1
30	4
31	2
32	4
33	2
34	6
35	2
36	5
37	4
38	4
39	2
40	5
41	1
42	7
43	1
44	7
45	5
46	3
47	2
48	4
49	2
50	4
51	3
52	6
53	3
54	6
55	4
56	7
57	4
58	8
59	2
60	9
61	2
62	8
63	3
64	2
65	3
66	7
67	4
68	7
69	1
70	7
71	4
72	7
73	1
74	7
75	4
76	9
77	7
78	8
79	2
80	9
81	3
82	6
83	2
84	6
85	3
86	7
87	2
88	8
89	3
90	7
91	4
92	6
93	8
94	9
95	4
96	6
97	3
98	9
99	5
100	8